Utility vehicle with parallel operated internal combustion engine and electric motor drivetrains

ABSTRACT

A utility vehicle includes a first axle, a second axle, an electric motor, an internal combustion engine, and a torque transfer device. The first axle is coupled to first and second wheels. The second axle is coupled to third and fourth wheels. The electric motor drives the first axle in a first direction and a second direction at different times. The internal combustion engine drives a transmission output shaft in one direction. The torque transfer device selectively drives the second axle in the first direction in response to rotation of the transmission output shaft in the one direction. The torque transfer device also selectively drives the second axle in the second direction in response to rotation of the transmission output shaft in the one direction.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.13/405,805 filed on Feb. 27, 2012, which claims the benefit of U.S.Provisional Application No. 61/588,880 filed on Jan. 20, 2012. Thedisclosures of the above applications are incorporated herein byreference in their entirety.

FIELD

The present application relates to hybrid utility vehicles having anelectric motor and an internal combustion engine drivetrains that canoperate separately and in parallel.

BACKGROUND

The background description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description that may nototherwise qualify as prior art at the time of filing, are neitherexpressly nor impliedly admitted as prior art against the presentdisclosure.

Utility vehicles, such as maintenance vehicles, cargo vehicles, shuttlevehicles, and golf cars include one primary mover, such as an electricmotor or an internal combustion engine. Torque output by the primarymover drives two or more wheels of the vehicle to propel the vehicle. Acontrol module may control operation of the vehicle based on one or moredriver inputs.

SUMMARY

A utility vehicle includes a first axle, a second axle, an electricmotor, an internal combustion engine, and a torque transfer device. Thefirst axle is coupled to first and second wheels. The second axle iscoupled to third and fourth wheels. The electric motor drives the firstaxle in a first direction and a second direction at different times. Theinternal combustion engine drives a transmission output shaft in onedirection. The torque transfer device selectively drives the second axlein the first direction in response to rotation of the transmissionoutput shaft in the one direction. The torque transfer device alsoselectively drives the second axle in the second direction in responseto rotation of the transmission output shaft in the one direction.

In other features, a method includes driving a first axle in a firstdirection and in a second direction at different times using an electricmotor. The first axle is coupled to first and second wheels of avehicle. The method also includes driving an output shaft of atransmission in one direction using an internal combustion engine. Themethod also includes selectively driving a second axle in the firstdirection in response to rotation of the transmission output shaft inthe one direction using a torque transfer device. At another time, themethod also includes selectively driving the second axle in the seconddirection in response to rotation of the transmission output shaft inthe one direction using the torque transfer device. The second axle iscoupled to third and fourth wheels of the vehicle.

In still other features, a utility vehicle includes an internalcombustion engine, an electric motor, an accelerator pedal, a positionsensor, a motor control module, and a throttle linkage. The internalcombustion engine drives a first set of wheels. The electric motordrives a second set of wheels. The first and second sets are different.The position sensor measures a position of the accelerator pedal. Themotor control module controls the electric motor based on the measuredposition. The throttle linkage mechanically connects the acceleratorpedal to a throttle valve of the internal combustion engine. Thethrottle linkage actuates the throttle valve as the accelerator pedal isactuated.

Further areas of applicability of the present disclosure will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples areintended for purposes of illustration only and are not intended to limitthe scope of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a functional block diagram of an example vehicle systemaccording to the present disclosure; and

FIG. 2 is a functional block diagram of an example vehicle controlsystem according to the present disclosure.

DETAILED DESCRIPTION

The following description is merely illustrative in nature and is in noway intended to limit the disclosure, its application, or uses. Thebroad teachings of the disclosure can be implemented in a variety offorms. Therefore, while this disclosure includes particular examples,the true scope of the disclosure should not be so limited since othermodifications will become apparent upon a study of the drawings, thespecification, and the following claims. For purposes of clarity, thesame reference numbers will be used in the drawings to identify similarelements. As used herein, the phrase at least one of A, B, and C shouldbe construed to mean a logical (A or B or C), using a non-exclusivelogical OR. It should be understood that one or more steps within amethod may be executed in different order (or concurrently) withoutaltering the principles of the present disclosure.

As used herein, the term module may refer to, be part of, or include anApplication Specific Integrated Circuit (ASIC); an electronic circuit; acombinational logic circuit; a field programmable gate array (FPGA); aprocessor (shared, dedicated, or group) that executes code; othersuitable hardware components that provide the described functionality;or a combination of some or all of the above, such as in asystem-on-chip. The term module may include memory (shared, dedicated,or group) that stores code executed by the processor.

The term code, as used above, may include software, firmware, and/ormicrocode, and may refer to programs, routines, functions, classes,and/or objects. The term shared, as used above, means that some or allcode from multiple modules may be executed using a single (shared)processor. In addition, some or all code from multiple modules may bestored by a single (shared) memory. The term group, as used above, meansthat some or all code from a single module may be executed using a groupof processors. In addition, some or all code from a single module may bestored using a group of memories.

The apparatuses and methods described herein may be implemented by oneor more computer programs executed by one or more processors. Thecomputer programs include processor-executable instructions that arestored on a non-transitory tangible computer readable medium. Thecomputer programs may also include stored data. Non-limiting examples ofthe non-transitory tangible computer readable medium are nonvolatilememory, magnetic storage, and optical storage.

Referring now to FIG. 1, a functional block diagram of an examplevehicle system is presented. A utility vehicle 100 includes an internalcombustion engine 102 that combusts an air/fuel mixture within one ormore cylinders (not shown). For example only, the vehicle 100 may be amaintenance vehicle, a cargo vehicle, a shuttle vehicle, a golf car, oranother suitable type of utility vehicle that is not designated for useon roadways.

A fuel system 104 provides fuel to the engine 102. Combustion of theair/fuel mixture within the engine 102 generates torque. The fuel maybe, for example, gasoline, diesel fuel, or another suitable type offuel. The engine 102 outputs torque to a transmission 106. For exampleonly, the transmission 106 may include a continuously variabletransmission (CVT) or another suitable type of transmission. Thetransmission 106 transfers torque to a rear axle 108 via a torquetransfer device 110. Specifically, the transmission 106 outputs torqueto the torque transfer device 110 via a transmission output shaft 111.When transferring torque output by the engine 102 to the torque transferdevice 110, the transmission output shaft 111 rotates in only onedirection.

The torque transfer device 110 includes a shift actuator 112 thatregulates operation of the torque transfer device 110 in one of threemodes: a forward mode; a reverse mode; and a neutral mode. When thetorque transfer device 110 is in the forward mode, rotation of thetransmission output shaft 111 in the one direction drives the rear axle108 to propel the vehicle 100 in a forward direction. When the torquetransfer device 110 is in the reverse mode, rotation of the transmissionoutput shaft 111 in the one direction drives the rear axle 108 to propelthe vehicle 100 in a reverse direction (opposite of the forwarddirection). When the torque transfer device 110 is in the neutral mode,the transmission 106 and the rear axle 108 are de-coupled, and torqueoutput by the transmission 106 is not transferred to the rear axle 108.The rear axle 108 drives one or more rear wheels, such as rear wheels109-1 and 109-2 (hereafter “rear wheels 109”). Alternatively, thetransmission 106 could effect forward, neutral, and reverse operation.

A starter/generator unit 114 selectively cranks and starts the engine102. A starter solenoid (not shown in FIG. 1) selectively engages thestarter/generator unit 114 with the engine 102 (e.g., with a flywheel,not shown). The starter/generator unit 114 draws electrical power from abattery pack 118 to crank and start the engine 102. The battery pack 118may include a plurality of individual batteries, such as batteries120-1, 120-2, 120-3, and 120-4, connected in series. Each of thebatteries 120-1, 120-2, 120-3, and 120-4 may be approximately 12 Volt(V) batteries such that the battery pack 118 provides approximately 48V. A greater or fewer number of batteries may be included to provide agreater or lesser voltage.

The starter/generator unit 114 may include a one way clutch that allowsthe starter/generator unit 114 to drive the engine 102, but not viceversa. The starter/generator unit 114 may automatically disengage fromthe engine 102 once a speed of the engine 102 reaches a predeterminedspeed during starting of the engine 102.

The starter/generator unit 114 is coupled to the rear axle 108 via asecondary rear drive system 122. For example only, the starter/generatorunit 114 may be coupled to the rear axle 108 by a belt 124 or a chain.The belt 124 may encircle a starter pulley 126 and an axle pulley 128.The starter pulley 126 is coupled to and rotates with a drive/drivenshaft (not shown) of the starter/generator unit 114. The axle pulley 128is coupled to and rotates with the rear axle 108.

When the starter/generator unit 114 is disengaged from the engine 102,the starter/generator unit 114 can impose a torque load on the engine102 (via the rear axle 108) to generate electrical power and charge thebattery pack 118. In other words, the starter/generator unit 114converts mechanical energy output by the engine 102 into electricalpower. The starter/generator unit 114 outputs electrical power atapproximately 48 V, the same voltage as the battery pack 118.

When the starter/generator unit 114 is disengaged from the engine 102,the starter/generator unit 114 can also directly drive the rear axle 108using electrical power from the battery pack 118 when the torquetransfer device 110 is in the neutral mode. This feature may allow thevehicle 100 to be operated in an all-electric four-wheel drive mode.

A vehicle control module 130 controls the mode of operation of thetorque transfer device 110 via the shift actuator 112. The vehiclecontrol module 130 controls operation of the starter generator unit 114.More specifically, the vehicle control module 130 controlscranking/starting of the engine 102 via the starter/generator unit 114.The vehicle control module 130 may also control charging of the batterypack 118 via the starter/generator unit 114. The vehicle control module130 may also control operation of the starter/generator unit 114, forexample, for operation in the all-electric four-wheel drive mode.

The vehicle 100 also includes an electric motor 131. The motor 131 canbe, for example, an alternating current (AC) motor, a direct current(DC) motor, an induction motor, a brushless motor, a brush-based motor,or another suitable type of electric motor. The motor 131 drawselectrical power from the battery pack 118 and drives a front axle 132.The front axle 132 drives one or more front wheels, such as front wheels134-1 and 134-2 (hereafter “front wheels 134”). In variousimplementations, more than one electric motor may be provided, and themotors may directly drive the front wheels 134. A motor control module136 controls operation of the motor 131. The motor control module 136also controls whether the motor 131 drives the front axle 132 to propelthe vehicle 100 in the forward direction or drives the front axle 132 topropel the vehicle 100 in the reverse direction. The motor controlmodule 136 controls the motor 131 based on signals from the vehiclecontrol module 130 and/or one or more other signals.

The motor 131 may be capable of outputting a greater amount of torquethan the engine 102. Additionally, a magnitude of sound (e.g., indecibels) produced by operation of the motor 131 is less than amagnitude of sound produced during operation of the engine 102. However,the engine 102 may be capable of achieving greater speeds than the motor131. Additionally, a range of the vehicle 100 (e.g., a maximum distancetraveled) when operated using only the engine 102 may be greater than arange of the vehicle 100 when operated only using the motor 131.

According to the present disclosure, in response to a user's selection,the vehicle 100 can be propelled in the forward direction or the reversedirection using only torque output by the motor 131. The vehicle 100 canalso be propelled in the forward direction or the reverse directionusing only torque output by the engine 102. The vehicle 100 can also bepropelled in the forward direction or the reverse direction using acombination of torque output by the motor 131 and the engine 102. When acombination of torque output by the motor 131 and the engine 102 isused, the motor 131 and the engine 102 may be controlled in tandem tobest utilize the greater torque output capability and the quieteroperation of the motor 131 with the greater speed capability and greaterrange of the engine 102.

Referring now to FIG. 2, a functional block diagram of a vehicle controlsystem 200 is presented. A user controls operation of the vehicle 100using input devices, such as an electric boost switch 204, a mode switch206, an OFF/forward/neutral/reverse (OFNR) switch 208, and anaccelerator pedal 210.

A user selects one of an OFF mode, a forward mode, a neutral mode, or areverse mode at a given time using the OFNR switch 208. The OFNR switch208 outputs a signal to the vehicle control module 130 that indicateswhether the OFF mode, the forward mode, the neutral mode, or the reversemode is selected.

The motor 131 and the engine 102 are both maintained OFF when the OFFmode is selected. When the forward mode is selected, the vehicle 100 isselectively propelled in the forward direction based on actuation of theaccelerator pedal 210. When the reverse mode is selected, the vehicle100 is selectively propelled in the reverse direction based on actuationof the accelerator pedal 210. When the forward mode or the reverse modeis selected, operation of the motor 131 and/or the engine 102 iscontrolled based on a selection input via the mode switch 206. When theneutral mode is selected, torque is not transferred from the motor 131to the front axle 132, and torque is not transferred from thetransmission 106 to the rear axle 108.

A user selects one of an electric mode, a both mode, or an engine (e.g.,gasoline) mode at a given time using the mode switch 206. The modeswitch 206 outputs a signal to the vehicle control module 130 thatindicates whether the electric mode, the both mode, or the engine modeis selected.

When the electric mode is selected, the engine 102 is maintained OFF,and the motor 131 may be operated to output torque to the front axle132. When the both mode is selected, the engine 102 may be operated tooutput torque to the rear axle 108, and the motor 131 may be operated tooutput torque to the front axle 132. When the engine mode is selected,the engine 102 may be operated to output torque to the rear axle 108,and the motor 131 may be maintained OFF.

A user selectively activates an electric boost by depressing the boostswitch 204 during operation in the engine mode. When the engine mode isselected and a user activates an electric boost by depressing the boostswitch 204, the engine 102 may be operated to output torque to the rearaxle 108 as described above, and the motor 131 may additionally beoperated to output torque to the front axle 132.

A user actuates (e.g., depresses and releases) an accelerator pedal 21to control torque to the front and/or rear axles 132 and 108. Useractuation of the accelerator pedal 210 from a resting position mayactuate a plunger switch 212. The plunger switch 212 outputs a signal tothe vehicle control module 130 indicating that the accelerator pedal 210is depressed relative to the resting position. The vehicle controlmodule 130 selectively engages the starter generator unit 114 with theengine 102 to start the engine via the starter solenoid 222. When thestarter/generator unit 114 is engaged with the engine 102, the vehiclecontrol module 130 may control the application of power to thestarter/generator unit 114 to crank and start the engine 102.

Actuation of the accelerator pedal 210 may also actuate a throttlelinkage 214. The throttle linkage 214 may regulate airflow into theengine 102 (e.g., via opening of a throttle valve) and fueling to theengine 102 when the engine 102 is ON. In this manner, actuation of theaccelerator pedal 210 controls torque output by the engine 102 while theengine 102 is ON.

Actuation of the accelerator pedal 210 also actuates a position switch216. The position switch 216 outputs a signal to the motor controlmodule 136 based on the position of the accelerator pedal 210. The motorcontrol module 136 may control a speed of the motor 131 based on theposition of the accelerator pedal 210. For example only, the motorcontrol module 136 may increase the speed of the motor 131 as the amountof depression of the accelerator pedal 210 relative to the restingposition increases.

A speed sensor 218 may be implemented to measure a speed of the motor131 and output a signal to the motor control module 136 and/or thevehicle control module 130 that is indicative of the measured speed. Themotor control module 136 may use the measured speed of the motor 131 asfeedback for controlling the motor 131. The vehicle control module 130may use the measured speed to determine, for example, whether the torquetransfer device 110 can be engaged without damaging the rear axle 108.

The vehicle 100 may also include an engine killing relay 224. Thevehicle control module 130 selectively actuates the relay 224 to enableoperation of the engine 102 at times when the engine 102 is off and toshut down the engine 102 at times when the engine 102 is running.

When the OFF mode is selected via the OFNR switch 208, the vehiclecontrol module 130 may control a switching device 220 such the motorcontrol module 136 is not powered. When one of the forward mode, thereverse mode, and the neutral mode is selected via the OFNR switch 208,the vehicle control module 130 may control the switching device 220 suchthat the motor control module 136 receives power from the battery pack118.

The vehicle control module 130 outputs a direction signal to the motorcontrol module 136 that indicates a selected direction. For example,when the forward mode is selected, the vehicle control module 130 setsthe direction signal to the forward direction. When the reverse mode isselected, the vehicle control module 130 sets the direction signal tothe reverse direction. When the neutral mode is selected, the vehiclecontrol module 130 sets the direction signal to neutral.

Table 1 below summarizes responses of the vehicle control module 130under steady-state conditions.

TABLE 1 OFNR Selection Mode Selection Drive direction of Motor 131Forward Electric Forward Forward Both Forward Forward Engine — ReverseElectric Reverse Reverse Both Reverse Reverse Engine —If the forward mode is selected via the OFNR switch 208 and the electricmode or the both mode is selected via the mode switch 206, the vehiclecontrol module 130 sets the direction signal to the forward direction,and the motor control module 136 selectively operates the motor 131 todrive the front axle 132 in the forward direction. If the reverse modeis selected via the OFNR switch 208 and the electric mode or the bothmode is selected via the mode switch 206, the vehicle control module 130sets the direction signal to the reverse direction, and the motorcontrol module 136 selectively operates the motor 131 to drive the frontaxle 132 in the reverse direction. If the engine mode is selected viathe mode switch 206, the motor control module 136 may maintain the motor131 OFF such that the motor 131 free wheels.

Table 2 below summarizes responses to depression of the boost switch 204under various circumstances.

TABLE 2 Boost Drive direction of OFNR Selection Mode Selection SwitchPressed Motor 131 Forward Electric — Forward Forward Both — ForwardForward Engine Electric on Forward Reverse Electric — Reverse ReverseBoth — Reverse Reverse Engine Electric on ReverseIf the neutral mode is selected via the OFNR switch 208, the motorcontrol module 136 may maintain the motor 131 OFF regardless of the modeselected via the mode switch 206. If the engine mode is selected via themode switch 206, the motor control module 136 operates the motor 131 inthe direction indicated by the direction signal in response to the boostswitch 204 being pressed. If the electric mode is selected via the modeswitch 206, no action may be taken in response to depression of theboost switch 204. No response may be taken because the motor 131 isalready being operated in the direction indicated when the electric modeis selected.

Table 3 below summarizes how the vehicle control module 130 positionsthe shift solenoid 112 under steady-state conditions. As describedabove, the shift solenoid 112 controls whether the transmission outputshaft 111 drives the rear axle 108 and, if the transmission output shaft111 is driving the rear axle 108, the direction in which thetransmission output shaft 111 drives the rear axle 108.

TABLE 3 OFNR Selection Mode Selection Shift Actuator Forward ElectricNeutral Forward Both Forward Forward Engine Forward Reverse ElectricNeutral Reverse Both Reverse Reverse Engine ReverseIf the forward mode is selected via the OFNR switch 208 and the bothmode or the engine mode is selected via the mode switch 206, the vehiclecontrol module 130 actuates the shift solenoid 112 such that thetransmission output shaft 111 drives the rear axle 108 in the forwarddirection. If the reverse mode is selected via the OFNR switch 208 andthe both mode or the engine mode is selected via the mode switch 206,the vehicle control module 130 actuates the shift solenoid 112 such thatthe transmission output shaft 111 drives the rear axle 108 in thereverse direction. If the electric mode is selected via the mode switch206, the vehicle control module 130 actuates the shift solenoid 112 to aneutral state such that torque is not transferred between the rear axle108 and the transmission output shaft 111.

Table 4 below summarizes how the vehicle control module 130 actuates theshift solenoid 112 under various circumstances while the vehicle 100 isin motion.

TABLE 4 OK to Shift Based Current Requested Current Requested on Actu-Electric Mode Mode Direction Direction Speed? ator Direction ElectricElectric F N Ok N F to N R Ok N F to R N F Ok N N to F R Ok N N to R R NOk N R to N F Ok N R to F Engine Engine or F N Yes F to N F to N or BothBoth No F to N F to N Engine Engine or N F Yes N to F N or Both Both NoN N Engine Engine or N R Yes N to R N to R or Both Both No N N EngineEngine or R N Yes R to N R to N or Both Both No R to N R to N EngineEngine or F R Yes F to R F to R or Both Both No F F Engine Engine or R FYes R to F R to F or Both Both No R R Engine Electric F F Ok F to N F orBoth N N Ok N N R R Ok R to N R Electric Engine or F F Yes N to F F BothNo N F Electric Engine or N N Yes N N Both No N N Electric Engine or R RYes N to R R Both No N R

N means Neutral, R means Reverse, and F means Forward.

The above is illustrative of a safety interlock feature provided by thevehicle control module 130 that prevent damage from being done to one ormore components, such as the transmission 106, the rear axle 108, theshift solenoid 112, the engine 102, etc. For example, when travelling inthe forward direction with the both mode via the engine 102 and themotor 131, the vehicle control module 130 may shift the shift solenoid112 from forward to neutral and disable the engine 102. The motor 131may continue to drive the vehicle 100 in the forward direction. In thismanner, the vehicle can be shifted on the fly from operation of theengine 102 (which may produce some noise) to operation with only themotor 131 (which may be silent or relatively silent). This ability maybe important to a customer. Once the shift solenoid 112 is in neutral,the vehicle control module 130 may not shift the shift solenoid 112again until the vehicle 100 comes to a stop.

The broad teachings of the disclosure can be implemented in a variety offorms. Therefore, while this disclosure includes particular examples,the true scope of the disclosure should not be so limited since othermodifications will become apparent to the skilled practitioner upon astudy of the drawings, the specification, and the following claims.

What is claimed is:
 1. A utility vehicle comprising: an internalcombustion engine that drives a first set of wheels; an electric motorthat drives a second set of wheels, wherein the first and second sets ofwheels are different; an accelerator pedal; a position sensor thatmeasures a position of the accelerator pedal; a motor control modulethat controls the electric motor based on the measured position of theaccelerator pedal; a throttle linkage that mechanically connects theaccelerator pedal to a throttle valve of the internal combustion engineand that actuates the throttle valve as the accelerator pedal isactuated; a starter/generator unit; a battery pack electricallyconnected to the starter/generator unit; a first axle structured andoperable to drive the first set of wheels; an axle pulley that isattached to the first axle and rotates with the first axle; a starterpulley that is attached to a shaft of the starter/generator unit androtates with the shaft of the starter/generator unit; and a couplingdevice structured and operable to drive the starter pulley, startershaft and starter/generator unit in response to rotation of the firstaxle and axle pulley generated via torque output by the internalcombustion engine such that the starter/generator unit generateselectrical power for charging the battery pack.
 2. The utility vehicleof claim 1 further comprising: a transmission that is structured andoperable to receive torque output by the engine and to drive atransmission output shaft in one direction; a torque transfer devicestructured and operable to selectively drive the first axle in a firstdirection and in a second direction in response to rotation of thetransmission output shaft in the one direction, wherein the first andsecond directions are different.
 3. The utility vehicle of claim 2further comprising a starter solenoid structured and operable toselectively engage the starter/generator unit with the internalcombustion engine to start the internal combustion engine, wherein thetorque transfer device is further structured and operable to selectivelydecouple the transmission output shaft from the first axle, and whereinthe starter/generator unit is structured and operable to selectivelyrotate the starter pulley in response to a determination that thetransmission output shaft is decoupled from the first axle and that thestarter/generator unit is disengaged from the internal combustionengine, and wherein the coupling device is further structured andoperable to drive the axle pulley and first axle in response to rotationof the starter pulley generated via torque output by thestarter/generator unit such that the first axle is driven via thestarter/generator unit.
 4. The utility vehicle of claim 2 furthercomprising: a switch structured and operable to output a signalindicating one of the first direction and the second direction; avehicle control module structured and operable: to selectively actuate ashift actuator such that the torque transfer device drives the firstaxle in the one of the first and second directions indicated by thesignal in response to rotation of the transmission output shaft in theone direction; and a motor control module structured and operable toselectively operate the electric motor to drive the second set of wheelsbased on the one of the first and second directions indicated by thesignal.
 5. The utility vehicle of claim 4 further comprising: a secondswitch structured and operable to output a second signal indicating oneof operation of only the electric motor, operation of only the internalcombustion engine, and operation of both the electric motor and theinternal combustion engine, wherein the motor control module is furtherstructured and operable to: control the electric motor based on thesecond signal, and control operation of the internal combustion enginebased on the second signal.
 6. The utility vehicle of claim 5 wherein:in response to the second signal indicating operation of only theelectric motor, the motor control module is structured and operable tocontrol operation of the electric motor and disable the internalcombustion engine; in response to the second signal indicating operationof only the internal combustion engine, the motor control module isstructured and operable to disable the electric motor and controloperation of the internal combustion engine; and in response to thesecond signal indicating operation of both the electric motor and theinternal combustion engine, the motor control module is structured andoperable to control operation of the electric motor and the operation ofthe internal combustion engine.
 7. The utility vehicle of claim 6further comprising a third switch structured and operable to output athird signal in response to actuation of the third switch, wherein, inresponse to the output of the third signal while the second signalindicates operation of only the internal combustion engine, the motorcontrol module is structured and operable to control operation of theelectric motor.
 8. A method for charging a battery bank of utilityvehicle, said method comprising: rotating an axle of a utility vehicleand an axle pulley attached to the axle, via torque generated by aninternal combustion engine of the vehicle; rotating a starter pulleyattached to a shaft of a starter/generator unit of the vehicle, viatorque generated by rotation of the axle and a coupling device operablyconnected to both the axle pulley and the starter pulley; and rotatingthe starter/generator shaft, via rotation of the starter pulley, suchthat the starter/generator unit generates electrical power for charginga battery pack of the vehicle utilizing the torque generated by rotationof the axle.